高山被孢霉高产花生四烯酸菌株的硫酸二乙酯诱变育种

摘要：花生四烯酸是一种ω-6系列长链多不饱和脂肪酸，具有重要的生物活性和营养作用。其传统来源有限且提取率低提取成本较高，导致其不能满足市场需求。微生物发酵法是制备花生四烯酸的新途径，此方法的核心问题是高产菌株的筛选。本论文以产花生四烯酸的高山被孢霉为出发菌株，采用硫酸二乙酯进行诱变，利用TTC染色法和气相色谱分析法分别进行初筛和复筛，最终获得了一株花生四烯酸高产菌株DES-25-4，其油脂得率可达到199 mg/g干菌体，比原始菌株提高了13.35%；其花生四烯酸含量达到11.26%，比原始菌株提高了9.52%；遗传稳定学实验表明，DES-25-4遗传稳定。本论文的研究可为花生四烯酸的生产提供菌株的选择。65906

毕业论文关键词：花生四烯酸，高山被孢霉，硫酸二乙酯诱变

Abstract：Arachidonic acid (AA) is a kind of long-chain polyunsaturated fatty acids of ω-6. It has an important role in biological activity. But the traditional source is limited and it costs too much to extract from them. Microbial fermentation is a new way to produce AA. The key is to screen high-yield strains in microbial fermentation. The aim of the experiment is to screen high-yield strains. In the experiment, Mortierella alpina producing AA was mutated by diethyl sulfate to improve the yield of producing AA. After screening repeatedly, a mutant DES-25-4 with high yield of lipid and AA was obtained. Comparing with the original strain, the yield of lipid increased by 13.35%, and the AA yield increased by 9.52%. Strain DES-25-4 had a good hereditary stability after several generations.

Keyword: Arachidonic acid, Mortierella alpina, Mutation by diethyl sulfate

1 前言 4

2 材料与方法 8

2.1 实验材料 8

2.2 实验方法 9

2.2.1 菌种保藏方法 9

2.2.2 菌种活化方法 9

2.2.3 硫酸二乙酯（DES）诱变方法 9

2.2.4 初筛方法 9

2.2.5 红四氮唑染色法（TTC）检测花生四烯酸含量方法 9

2.2.6 复筛方法 10

2.2.7 突变株遗传稳定性的测定方法 11

3 结果与分析 12

3.1 硫酸二乙酯诱变致死率结果 12

3.2 硫酸二乙酯诱变的初筛结果 12

3.3 硫酸二乙酯诱变的复筛结果 15

3.4 突变菌株的遗传稳定性结果 15

4. 结论与展望 17

4.1 结论 17

4.2 展望 17

参考文献 18

致谢 20

1 前言

1.1 花生四烯酸及高山被孢霉的简介高山被孢霉高产花生四烯酸菌株的硫酸二乙酯诱变育种:http://www.youerw.com/shengwu/lunwen_73636.html